Trailer coupling



May 2, 1961 G. BOLMES TRAILER COUPLING Filed May 15, 1957 V/l/l//l//l//A INVENTOR.

United States Patent O TRAILER COUPLING Henry G. Bolmes, West Allis,`Wis., assignoto The Fulton ompany, West Allis, Wis., a corporation of Wiscons i V Filed May '15, 1957, Ser. No. 659,404'

' Claim. c. 280-512 The present invention relates generally to improve- ?atentati Ma a, 1961- accidental release while still being readily manipulable to separate the coupling members when desired. i

Still another important object of the present invention;` i is to provide an improved ball and socket coupling ac f tuating cam lever and latch assemblage which maybe readily constructed at moderate cost, and which functions to insure maximum safety of the coupling to which it is applied.

These and other morespecific objects and advantages s of the inventionwill be apparent from the following detailed description. i

A clear conception of the features constituting the present improvement, and of theconstruction and opments in vehicle couplings, and it relates more specifically to improvements in the Construction and operation of ball and socket trailer couplngscf the type having a movable ball retainer cooperable with a socket member to hold the ball member within the socket.

The primary object of my in'vention is to provide a simple, compact and durable ball and socket coupling which is highly effective in operation with utmost safety.

It has heretofore been proposed as shown anddescribed in U.S. Patent No. 2,170,980, granted August 29, 1939 to Joel R. Thorp et al., to provide a ball and socket trailer coupling having a swingable ball retainer operable by a cam lever pivotally attached to a retainer actuating rod and coacting with a hearing plate testing' on top of the socket member to Swing and maintain the ball retainer in active engagement with the ball member of the coupling. The cam lever of this 'prot patented coupling was adapted to be normally 'positively locked into horizontal ball confining condition by means of a padlock, which when released, would permit the cam lever to be swung into upright ball releasing position, and many of these quickly releasable but normally locked coupling assemblages were marketed and successfully used.

In order to avoid necessity of utilizing a padlock and key in order to effect locking of such ball and socket trailer couplings, it has also been frequently proposed to provide some kind of a spring pressed latch carried by the retainer actuating lever and which is adapted to`snap into active lever and ball retainer holding condition whenever the lever, is swung into such active position. 'Whilesuch an automatically functioning holding latch acts, as a safety device when' no padlock is, employed, it does not prevent unauthorzed release of`the coupling, a'ndthe pn'or safety latches have -all been objectionable either 'because they were too complicated and difficultto release,` or because they protruded from the main retainer actuat-.

ing lever and' were subject to be struck and accidentally actuated to release the coupling members when in normal;

It is therefore an important object of my invention 55 use;

to provide 'a quickly releasable ball and socket trailer eration of a commercial ball and socket trailer couplingp embodying the invention, may be had by-referring to,the V drawing accorrpanying and forming a part of this spec- V i e hereinas having been embodied in an automobila ball and socket trailer coupling of the type wherein the hall;

' member is adapted to be attachedto the rear bumper of thehauling vehicle while the socket member is normally secured to the draft tongue of a trailer, it is not the intent to restrict the use of the improved features to` such couplings; and it is also contemplated that descriptive terms employed `herein be given the broadest interpretation consistent with the disclosure. v

Referring to the drawing', the ball and socket trailercoupling shown` therein comprises in general, arsphere or ball member 5 having a lower mountingbolt 6; a

socket member 7 having a spherical internal zone sur e face 8 adapted to coact with the front of the ball mem-- 5 v ber 5 and being provided with an inverted U-shaped' eritension 9 formed for attachment to a trailer draft tongue; a ball retainer 10 swingably Suspended from a transverse shaft 11 secured to thesidewalls of :the coupling meme.

ber 7` and having a spherical zonesurfacelz engageable with thegrear of the ball member 5 to maintain the. ball within the socket formed by the surface 8;-a bearing plate 13 resting upon the top of the socket me rnberj 7; a ball retainer actuating bolt 14 coacting ,with thez retainer 10 through lower and upper springs 15, '16. re-

coupling' of the type 'shown in thetabove'identified prior patent, but embodying an improved cam lever and safety latch which elimnates all of the objectionable features of the prior couplings.

Another important object -of this invention is to provide a ball and socket coupling member releasingrand con-' nectng'cam leverwhich is extremely durable in construction, and 'whichwill not'becriie'distorted and ineffective due to the normal abuse to which such couplings are subjected.

A further important object of the invention is to provide an improved automatically functioning holding latch for the cam actuating lever of such ball and socket couplngs, which is substantially hidden or concealed within the lever itself and is therefore protected .against spectively, and havingan upperflattened portion extend ing through'alined openings 17, 18 in thersocketmem ber 7 and hearing platels respectivel'y; ,aretainermnipulating lever: 19 pivotally attached to the upper endi i of the boltf14 byfi pin '20 and havingopposite the leverlmnipulating handle 24; anda spring pressied walls 'zl by a pivot pinca' and `'having one end 27 operable with a notch 28 at the extreme upper end of the' bolt. 14 while its opposite swinging end 29 extends toa ward and' extends -only slightly 'above the handle 24.

The ball member 5, socket member 7, retainer 10, hearing plate l3, lever 19, and' latch 25 may all formed of durable sheet metal with the aid of'punch'es and diesand the ball retainer 10 is provided withrear;

While the invention `has been shown and described side, walls 21 provided 'with' lower cam surfaces 2 2 coopera i ble with' the bearing ;plate"13 and, which ?are configuous' With a' lower'transverse web 23 formedintegralfwith: the walls 21 andextend awayfrom the latter toward i spring 15 which embraces the bolt 14. between the nut 32 and the ball retainer 10 is a relatively strong spring which normally presses the retainer surface 12 with uniform pres-sure, while the upper spring 16 which is interposed between the retaincr 10* and the top of the socket member 7 is much lighter and merely functions to assist gravity in lowering the retainer when the lever 19 is sw ung into uprightinactive position. I i i The medial flat portion of the rod 14 andthe adjacent portions of the walls 21 of the cam lever 19, are also provided with holes 33 :which are alined when the lever is in active horizontal position', and these alined holes 33 are adapted to receive a padlockin order to positively lock 'the ball member within the socket member 7. The horizontal holding latch 25 which is conned between and protected by the side walls 21 of the cam lever 19, has its latching end 27 urged into active latching position by a spring 34 interposed between the web 23 and the opposite` end 29 of the latch, and this latch 25 may obviously be readily released by the palm of the hand of an operator grasping the handle 24` of the cam lever 14.

When the improved ball and socket trailer coupling has been properly constructed and assembled as hereinabove described, the ball member 5 may be firmly attached to a draft vehicle with the aid' of its mounting bolt 6, and the socket member 7 may be likewise attached to the tongue of a trailer by means of bolts passing through openings in its rear extension 9, in a well known manner. bers 5, 7, it is only necessary for the operator toswing the retainer manipulating cam lever 19 into upright position, whereupon the ball retainer will swing downwardly about the shaft 11 sufficiently to permit the ball` member 5 to be inserted within the socket of the member 7. The operator may thereafter Swing the lever 19 rearwardly about the pivot into horizontal position as shown in the drawing, whereupon the rod 14 will be elevated by the cam surfaces 22 coacting with the bearing plate 13, and will swing the retaner 10 upwardly about the shaft 11 to cause its spherical zone surface 12 to force the ball into resilient engagement with the socket surface 8.

When the lever 19 approaches its horizontal active condition, the end 27 of the latch 25 will ride over the extreme upper end of the bolt 14, and as the lever 19 reaches its final ball rctaining position the spring 34 coacting with the latch 25 becomes effective to automatically Swing the latch end 27 into holding engagement with the notch 28 at the upper end of the bolt 14. If so desired, a padlock may also be appliedto the alined holes 33 in the rod 14 and lever walls 21; and when it becomes desirable to uncouple the coupling it is only necessary to remove the padlock if used, and,for the operator to thereafter grip the lever handle 24 while simultaneously depressing the adjacent latch end 29 and for him to Swing the lever 19 forwardly about the pivot 20 into upright position. i

From the foregoing detailed description, it should be appa'ent that the present invention in fact provides a ball and socket coupling which is simple and durable in In order to thereafter couple the mem-` construction, and readily manipulable to quickly either couple or uncouple the vehicles. Most of the parts of the improved assemblage may be accurately produced of durable sheet metal with the aid of punches and dies, and the improved construction of the actuating lever 19 with sturdy opposite side walls 21 formed integral with a lower transverse inclined web 23 which extends from the handle 24 into close proximity with the cam surfaces 22, not only provides an exceptionally strong lever but also forms an 'upwardly unobstructcd channel space within which the latch 25 is normally contined. The improved formation and disposition of the latch 25 is also important since it eliminates excessive extension or projec tion of this latch beyond the confines of the lever 19, and which might otherwise be subject to engagement with external objects tcnding to disengage the latch during normal use of the coupling; but the improved latch 19 is still readily manipulable whenever the operator grasps the lever handle 24. The improved couplings have proven highly satisfactory and successful in actual use, and may be manufactured in various sizes for diverse uses.

It should be understood that it is not desired to limit this invention to the exact details of Construction of the trailer coupling herein specifically shown and described, for various modifications within the scope of the appended claim may occur to persons skilled in the art.

I claim:

In a ball and socket trailer coupling of the type having a retractable ball retainer cooperable with a socket member to hold the ball member within the socket, a vertically reciprocable rod element having its lower portion formed for cooperation with the ball retainer to move the latter into active ball rctaining position while its upper portion projects upwardly through and beyond the top of the socket member and is provided with a notch at its extreme upper end, a bearing plate surrounding the medial part of said rod and resting upon said socket member top, a one-piece sheet metal lever having laterally spaced side walls provided with lower cam surfaces coacting with said hearing plate and also having a transverse lower web inclined toward and terminating in close proximity to said cam surfaces while being formed integral with the side walls to provide a lever having an upwardly open and unobstructed U- shaped transverse cross-section, said lever walls remote from said cam surfaces being pivotally attached to said rod below said notch and said lever having a manipulating handle formed integral with said side walls and with the upper end of said web and being alternately swingable to cause its cam surfaces to raise said ball retainer into active ball rctaining position and to etfect release oi the retainer, an approximately horizontal looking latch pivotally secured to said lever side walls between said rod and said handle and having one end engageable with said notch to hold said retainer in said active position while its opposite manipulating end is provided with a recess facing said web and is swingable toward the web bet wcen said lever side walls directly adjacent to said lever handle, and a helical compression spring interposed between said lever web and said latch recess.

References Cited in the file of this patent UNITED STATES PATENTS 2,162,0S2 Bird June 13. 1939 2,726,099 Nunn Dec. 6, 1955 

